Methods and compositions using a petroleum oil fraction



United States Patent California No Drawing. Filed July 3, 1963, Ser. No. 292,753 10 Claims. (Cl. 10727) This invention relates to pesticides and more particularly to petroleum pesticides which are effective against spider mites, mite eggs, scale insects and certain other pests.

Petroleum oil fractions have long been used as pesticides, particularly highly refined oils prepared from base oils similar to light lubricating stock. The usual procedure is to emulsify a few parts oil in a hundred parts water and spray the mixture on the pest habitat. The oil is dispersed in the Water by means of mechanical agitation and an emulsification agent may be used.

Higher boiling fractions have been regarded as highly phytotoxic and hence only certain lower boiling fractions are customarily used as spray oils. Oils which are sprayed directly on foliage and fruit (highly refined spray oils) are also treated to remove most of the unsaturated hydrocarbons and other phytotoxic ingredients. Phytotoxicity is minimized if the oil is less than 10% unsaturated.

Spray oils are most commonly identified by boiling range properties and degree of refinement, the latter expressed as unsulphonated residue, and these properties are determined by standardized test procedures accepted by the industry, which test procedures will be referred to below.

It is an object of this invention to provide an insecticide and acaricide derived from a petroleum oil fraction of somewhat higher boiling range than has been generally used heretofore.

It is a further object of this invention to provide such a pesticide which is, in certain respects, superior to those which have been available heretofore, especially with respect to the quantity used to achieve the results desired.

Further objects and advantages of this invention, if not specifically set forth, will become apparent during the course of the description which follows.

Generally, this invention comprises a composition and method for use thereof for controlling pests of the orders Insecta and Acarina, the composition being a high-boiling petroleum fraction characterized in that about 90 weight percent thereof boils within the range of about 550 F. to about 650 F. under a vacuum of 10 mm. of mercury, about 5% boiling above and 5% below this range. This highly refined petroleum fraction is applied to the pest habitat in the form of an emulsion of oil in water, the oil preferably representing between 0.1 and 2 weight percent of the total composition. This mixture is particularly effective against the aforementioned pests and is relatively non-phytotoxic. It preferably incorporates a low boiling aliphatic petroleum fraction such as kerosene or other diluent such as an oil miscible ketone or alcohol for ease of application and to reduce penetration into plant tissues.

The boiling range is given according to ASTM Designation D-ll60 mm. Hg vacuum) for the oils of this invention since cracking occurs when atmospheric pressure distillation is employed because of the higher distillation temperatures needed. However, translation of the D-l160 figures into terms of ASTM designation D-447 (atmospheric pressure) by use of a conversion table yields a range of 844 F. to 953 F.

More particularly, it has been discovered that a highly refined petroleum oil fraction having a high, narrow boil- 3,285,201 Patented Nov. 15, 1966 ing range is unusually effective as an insecticide and miticide and hence may be used in quantities, relative to the customary water carrier, which are unusually low.

It had generally been thought that oils of extremely high viscosity and high boiling range may not be used on foliage because of their adverse effects on plant life.

Prune trees, which are highly susceptible to injury from oil, were selected for mite control experiments. A standard comparison test oil was used which was a typical summer spray oil of light-medium grade. The preparation contained about 99% weight percent oil and about /2 percent emulsifier to produce what is called a summer soluble oil. This was used at the rate of one and onehalf gallons of oil to 100 gallons of water and sprayed at the rate of about 5 gallons of spray mixture per tree. Poor results were obtained with this treatment as indicated by severe mite injury to the foliage. There was also direct injury from the oil as exhibited by leaf spotting, chlor-osis and partial defoliation.

Another experiment was conducted at the same time on adjacent trees in which a highly refined petroleum fraction, about of which boiled above 550 F. at 10 mm. Hg vacuum, and 5% of which boiled in excess of 650 F. (ASTM D-1l60), was used in 'a similar manner. A preparation otherwise similar to that described above which was applied in the same manner was exceptionally effective, even at low dosage rates. Preparations incorporating this high boiling fraction were highly effective against mites at one-half the standard dosage rate of the comparison oil and, equally important, caused only minor injury to the foliage or other plant parts.

It has been found that the highly refined petroleum oil fractions of this invention are unusually effective when mixed with a low boiling, non-phytotoxic, aliphatic petroleum fraction in such proportions that the viscosity is reduced to a more desirable range for maximum effectiveness against certain pests. Aliphatic hydrocarbons in the kerosene boiling range, especially 300 F. to 500 F., are preferred. Other solvents or diluents which may be used to promote ease of handling, ready emulsification, improved spreading on certain plant parts, reduced penetration into plant tissues, and improved overall effectiveness against insects, are the ketones such as 1,4-dioxane, isophorone, and 4-methoxy-4-methyl pentanone-Z, the alcohols such as 2-ethyl hexanol, iso-octanol-(mixed isomers), and 4-methoxy-4-methyl pentanol-2, and tributyl phosphate.

The following examples will serve to further illustrate the invention.

EXAMPLE I A spray oil was prepared consisting of a highly refined oil having a viscosity of 1035 seconds, Saybolt Universal at F unsulphonated residue of 91%, a calculated molecular weight of 452 and a boiling range characterized by 5% distilling at less than 551 F. and 95% distilling at less than 648 F. at 10 mm. Hg (ASTM 1160). The preparation, containing sufficient emulsifier to create a uniform mixture in the spray tank with agitation, was applied to prune trees at rates of 0.17, 0.33 and 0.67 gallon of oil per 100 gallons of water. This preparation was moderately effective at the lower rates and highly effective at the highest rate, even though this was less than half the dosage rate of the standard comparison oil which was used at the rate of 1.5 gallon per 100 gallons of water.

EXAMPLE II A blend was prepared containing 67% of the oil of Example I and 33 of an aliphatic petroleum solvent having an atmospheric pressure boiling range of 382 F. to 489 F. Mixing the insecticidal oil with the light aliphatic solvent reduced the viscosity of the oil to a point which permitted it to spread uniformly over the surface of the plant parts and to penetrate more readily into the insect tissues. Dilution with the solvent thus permitted a reduction in the total quantity of pesticidally eifective oil needed for insect and mite control.

Results of this preparation, used at a total dosage rate of 1.0 gallon of oil-solvent mixture per 100 gallons of water, showed that this mixture was more effective than either a standard treatment of light medium oil or a product designated as extra heavy grade.

EXAMPLE III I A blend was prepared containing 75% of the oil of Example I and 25% of 4-methoxy-4-methyl pentanol-2 solvent or diluent, plus about 0.5% emulsifier. This blend was mixed in water with agitation at the rate of 0.5 gallon per 100 gallons of water and sprayed on citrus trees. Scale insects were adequately controlled even at this low dosage; there was no injury to fruit or foliage.

EXAMPLE IV A flowable emulsion concentrate was prepared containing 81.7% by volume of the oil of Example I, the re- 'mainder of the concentrate being water and emulsifier. This preparation was mixed with water at the rate of 0.5 gallon per 100 gallons of water and sprayed on apple trees and navel orange trees. There was no injury to foliage or fruit.

In the table which follows, there appears a comparison of the physical properties of a standard oil identified as light-medium oil with the fraction of this invention identified as high-boiling oil. Below there is set forth a table indicating the temperatures (ASTM D-ll60 or 10 mm. Hg) at which various portions of the oil were distilled over. Corresponding D-447 (atmospheric pressure) figures were read from a standard table and appear in a parallel column. It will be seen, therefore, that a new and useful insecticidal and miticidal composition has been provided which combines the advantages of high pesticidal activity with ease of handling but without the attendant disadvantage of serious phytotoxicity normally encountered with heavy spray oils.

Propertzes f petroleum oil samples Light Medium High Boiling Oil Oil Gravity, A.P.I 29.0 24. 8 Specific gravity at 60l60 F- 0.88 0. 9052 Unsulphonated residue, percent (ASTM D 483) 92 91. 2 Viscosity, seconds at 100 F. (AS'IM D 445-53 and 44653) 74 1, 035 Molecular weight, approximate 289 452 Distillation, ASTM D-447 1 D-1160 2 D447 3 560 523 812 580 551 844 588 555 849 599 560 855 609 566 861 619 573 869 630 577 874 644 585 883 658 595 894 679 605 905 708 629 932 o 733 648 953 734 685 994 Range, 5% to 95% 153 97 109 1 Distillation at atmospheric pressure.

2 Distillation under vacuum at mm. Hg pressure. 3 Calculated conversion to atmospheric distillation.

I claim:

1. An insecticidal and acaricidal composition comprising water and a substantial proportion of a petroleum fraction characterized in that it has a minimum unsulfonated residue of not less than about percent and about 90 weight percent thereof boils within the range about 550 F.-650 F. under a vacuum of 10 mm. Hg, said petroleum fraction representing between about 0.1 and 2 weight percent of the said composition.

2. The composition of claim 1 wherein the petroleum oil fraction contains 0.2 to 2.0 weight percent of an oilsoluble emulsifier, based on the weight of said petroleum oil fraction.

3. An insecticidal and acaricidal composition comprising water and a substantial proportion of a petroleum oil fraction, characterized in that it has a minimum unsulfonated residue of not less than about 90 percent and about 90 weight percent thereof boils Within the range about 550 F.650 F. under a vacuum of 10 mm. Hg, together with between about 2 and 25 weight percent, based upon the weight of the said petroleum oil, of an oil-miscible diluent, said petroleum oil representing between about 0.1 and 2 weight percent of the said composition.

4. The composition of claim 3 wherein said diluent is a compound selected from the class consisting of 1,4- dioxane, isophorone and 4-methoxy-4-methyl pentanone-2.

5. The composition of claim 3 wherein the diluent is an aliphatic petroleum solvent having an atmospheric petroleum solvent boiling range within about 300 F. to 500 F.

6. The composition of claim 3 wherein the diluent is an alcohol selected from the class consisting of 2-ethyl hexanol, iso-octanol, iso-decanol and 4-methoxy-4-methyl pentanol-2.

7. A method of killing pests of the order Insecta and Acarina comprising: applying to the pest habitat a petroleum. oil fraction characterized in that it has a minimum unsulfonated residue of not less than about 90 percent and about 90 weight percent thereof boils within the range of about 550 F.'-650 F. under a vacuum of 10 mm. Hg.

8. The method of claim 7 wherein the petroleum oil fraction contains between about 0.2 and 2.0 weight percent of an oil-soluble emulsifier based on the weight of said petroleum oil fraction.

9. A method of killing pests of the order Insecta and Acarina comprising: applying to the pest habitat a composition containing water and a petroleum oil fraction characterized in that it has a minimum unsulfonated residue of not less than about 90 percent and about 90 weight percent thereof boils within the range about 550 F.650 F. under a vacuum of 10 mm. Hg, together with water, said petroleum oil fraction representing between about 0.1 and 2 weight percent of the said composition.

10. A method of killing pests of the order of Insecta and Acarina comprising spraying vegetation subject to such pests with an aqueous emulsion of a petroleum oil fraction having a boiling range such that not less than about 5% boils below about 550 F. and not more than about 5% boils above about 650 F. at a pressure of ten millimeters of mercury, said petroleum oil fraction containing not less than about90 percent of unsulfonated residue.

References Cited by the Examiner 3,138,896 6/1964 Millikan "167-27 JULIAN S. LEVI'IT, Primary Examiner.

S. J. FRIEDMAN, Assistant Examiner. 

7. A METHOD OF KILLING PETS OF THE OUTER INSECTA AND ACARINA COMPRISING: APPLYING TO THE PEST HABITAT A PETROLEUM OIL FRACTION CHARACTERIZED IN THAT IT HAS A MINIMUM UNSULFONATED RESIDUE OF NOT LESS THAN ABOUT 90 PERCENT AND BOUT 90 WEIGHT PERCENT THEREOF BOILS WITHIN THE RANGE OF ABOUT 550*F.-650*F. UNDER A CACUUM OF 10 MM. HG. 